Drilling mechanism



July 14, 1942 F. M. SLATER DRILLING MECHANISM Filed. April 26. 1840 INVENTOR Fred M S'hzter HIS A'ITORNEY Patented July 14, 1942 i U'NITED STATES PATENT OFFICE 2,289,465

DRILLING MECHANISM Fred M. Slater, Phillipsburg, N. J-., assignor to Ingersoll-Rand Company, New York, N. Y., a

corporation of New Jersey Application April 26, 1940,. Serial No. 331,730

5 Claims.

This invention relates to drilling mechanisms, and more particularly to a drilling mechanism in which the drilling motor is supported by a pressure actuated expansible leg that may serve both as a support and a feeding. mechanism for the drilling motor.

One object of the invention is to minimize the effort required of the operator for guiding the rock drill and supporting it with respect to the Work. e

Other objects will be in part obvious and in part pointed out hereinafter.

In the drawing accompanying this specification and in which similar reference numerals refer to similar parts,

Figure 1 is an elevation, partly in section, of a drilling mechanism constructed in accordance with the practice of the invention,

Figure 2 is an elevation, partly in section, taken through Figure 1 on the line 2+-2, showing the pivotal connection between the rock drill and the feeding mechanism,

Figure 3 is a transverse view taken. through Figure 1 on the line 33, showing a valve mechanism for controlling the supply of pressure fluid to the feeding device, and

Figures 4 and 5 are transverse views taken through Figure 3 on the lines 4-4 and 5-5, respectively, showing the throttle valve in one of its limiting positions.

Referring more particularly to the drawing, 2-0

designates, in general, a drilling mechanism comprising a rock drill 2| and a feeding mechanism 22 for supporting the rock drill in correct operative relationship with the rock 23 and to apply pressure to the rock drill for advancing it in accordance with the penetration of the working implement 24, actuated by the rock drill, into the rock 23.

The rock drill 2| is illustrated as being of a conventional type known to the trade as a Jackhamer having handles or grip portions 25 that are grasped by the operator for supporting and guiding the rock drill. The rock drill has the usual casing parts comprising a cylinder 26 and front and back heads 21 and 28, respectively,

clamped to the cylinder 26 by the usual side rods 29.

The back head 28 supports the grip members 25 and houses a throttle valve, only the lever 30 of which is shown, for controlling the supplyof pressure fluid to the rock drill, and the front head 21 serves as a guide for the working implement 24 and has attached thereto a retainer 3| that partly encircles the working implement 24 to retain it in the front head.

The feeding mechanism 22 serves as a support for the rock drill 2| and to assist in applying pressure to the rock drill for maintaining it in the correct operative relationship with the workrest.

periphery of the plug 39.

ing implement 24. In the form illustrated, the cylinder 32 of the feeding mechanism is the stationary element and has a pointer 33 attached to its lower end to engage a floor 34 or other support upon which the drilling mechanism may Within the cylinder 32 is a piston 35 having a rod 36 that projects from the upper end of the cylinder 32 and has a passage 3! for'conveying pressure fluid. into the cylinder 32 beneath the piston 35 for extending, the. feeding mechanism.

The passage 31 extends from the lower end of the piston assembly into the portion of the rod lying outside of the cylinder. 32 and opens into a branch connection 38 shown as being an integral portion of the rod 33. A plug 39 is threadedly connected to. the branch 38 with one end and its other end is attached, by means of a coupling 40, to a hose 4| leading from a suitable source of pressure. fluid supply.

The plug. 3.9 constitutes a part of the valve mechanism whereby the pressure value within the feeding mechanism i controlled and has a pair of passages 42 and 43 extending part Way therethrough and communicating respectively With the hose 4| and the branch connection 38. The passages 42 and 43 have lateral branches 44 and 45, respectively, at their inner ends opening into the periphery of the plug, and the surface of the plug adjacent the branches 44 and 4.5 is tapered to provide a seat 46 for a rotary sleeve valve 41 serving to control the branches 44 and 45.

The bore. 48 in the sleeve valve 4'!v is normally maintained in sealing relationship with the tapered surface 46 by a spring 49 interposed between the valve and the coupling 40, and on one side of the bore 48 is a longitudinally extending groove 50 toafford communication between the branches 44 and 45 in what. may be termed the open position of. the valve 41.

As a preferred arrangement the branch passage 44 opens into a partly annular groove 5| in the In length, the groove may substantially equal the width of the slot 53 and the portions of the groove 5| lying on opposite sides of the branch 44 are preferably tapered to diminish the flow. area of the groove towards its ends. Thebranch passage 45 also opens into a groove 52 partly encircling the plug 39, and in the valve 4'! is a vent 53 for communieatingthe groove 52, with the atmosphere.

The connecting device between the feeding mechanism and the rock drill is preferably attached to an intermediate portion of the rock drill. It comprises a head 54 having a smooth, cylindrical socket 55 to slidably receive the free end 56 of the piston rod 35. Sufficient clearance should exist between the Wall of the socket 55 and the end 55 of the rod to permit the head 54 to be readily placed upon the rod or detached therefrom. As a preferred arrangement an annular groove 51 is formed in the wall of the socket 55 to accommodate a pin 53, arranged laterally in the side of the rod 36, and a slot 59 extends along one side of the socket 55 to the annular groove 51 to permit the entrance of the pin 58 into the groove 51. Ample clearances exist between the pin 53 and the cavities in the head 54 to permit of unhampered movement of the pin which serves merely to prevent accidental removal of the head 54 from the piston rod.

On the upper end of the head 54 are a pair of lugs 60 spaced with respect to each other to accommodate therebetween a bearing block 6| that is pivotally connected to the lugs by a pin 62 having an annular groove 63 intermediate its ends, and in the upper portion of the bearing block BI is a bore 64 that lies at right angles to the pin 62 and directly adjacent thereto. A bushing 65 disposed in the bore 64 lies in the annular groove 63 to prevent endwise movement of the pin 62.

The bushing 65 is preferably slightly longer than the portion of the bearing block wherein it lies and serves as a bearing surface for a bolt 66 between the head 61 of which and the bushing 65 is arranged a washer 68.

On the opposite end of the bolt are disposed a pair of support arms 69 which form the sole support for the rock drill and have apertures 73 to receive the bolt and a nut H threaded on the bolt 66 clamps the support arms securely against the end of the bushing 65. The support arms are of arcuate shape. They partly encircle the rock drill 2| and in the upper surface of each support arm is a groove 12 to receive a side rod 29. Suitable clamping members 13 overlie the side rods and are forced into clamping relationship therewith by nuts 14 on bolts 15 extending through the clamping members and threaded into the arms 69.

The operation of the device is as follows: Whenever it is intended to drill a hole in the rock 23 the drilling mechanism is so positioned that the feeding mechanism inclines toward the work and the valve 41 is rotated to place the groove 50 in communication with the grooves and 52. Pressure fluid will then flow from the passage 42 into the passage 43 and associated channels beneath the piston 35 and extend the feeding mechanism.

Upon the introduction of pressure fluid into the feeding mechanism a portion of the pressure fluid flowing through the groove 50 will, of course, escape through the vent 53 to the atmosphere but, owing to the small flow area of the vent, the loss of pressure fluid thus occasioned is negligible. Thus, if it be intended merely to elevate the drilling mechanism and operate the rock drill without the application of feeding pressure thereto other than that applied by the operator the valve 4'! need be rotated only a sufficient distance to assure supporting pressure beneath the piston 35. This balance may be nicely maintained by adjusting the valve 41 to admit the required amount of pressure fluid into the feeding cylinder for extending the feeding mechanism accordingly as the working implement penetrates the Work.

When operating under these conditions only enough pressure fluid is admitted into the feeding mechanism to maintain it in an extended supporting position. If, on the other hand, it be desired to use the force of the feeding mechanism for advancing the rock drill toward the Work the valve 41 may be shifted into a position to establish a wide area of communication between the passages 42 and 43 so that the volume of pressure fluid passing through the groove 53 exceeds the capacity of the vent 53. The pressure beneath the piston 35 will then increase and tend to elevate the rock drill. This pressure may be conveniently balanced with downward pressure upon the grip members 25 by the operator and the rock drill will be advanced toward the Work by the resultant of these two forces.

Thus, instead of supporting the weight of and holding the rock drill in the correct relationship with the work the operator need merely apply sufficient downward pressure upon the rear end of the rock drill to maintain it in substantial alignment with the desired course of the cut. In practice, this has been found to be quite considerably less fatiguing to the operator than the prior method of manually supporting and guiding a rock drill of the hand-held type.

I claim:

1. A drilling mechanism, comprising a rock drill, a fluid actuated feeding mechanism for the rock drill comprising a pair of telescopically arranged members, a head on the end of one of the members, a bearing block, a pivot extending through the bearing block and the head, a pair of arms aflixed tothe rock drill, and means for securing the arms to the bearing block.

2. A drilling mechanism, comprising a rock drill, a fluid actuated feeding mechanism for the rock drill comprising a pair of telescopically arranged members, a head on the end of one of the members, a bearing block having a pair of bores arranged at right angles to each other, a pivot in the head and one of the bores, a pair of arms affixed to the rock drill, a pivot in the other bore extending through the arms, and means for retaining the arms on the last mentioned pivot.

3. A drilling mechanism, comprising a rock drill, a fluid actuated feeding mechanism for feeding and supporting the rock drill comprising a pair of telescopically arranged members, means for pivotally connecting the rock drill to one of the members, and valve means for controlling the supply of pressure fluid to the feeding means to partly extend the said feeding means and to maintain a suitable pressure within the feeding means for holding the said feeding means thus partly extended.

4. A drilling mechanism comprising a rock drill, a feeding mechanism for the rock drill, a pivot on the feeding mechanism, a pair of support arms on the rock drill attached swingably to the pivot and forming the sole support for the rock drill, and means for locking the sup port arms to the pivot.

5. A drilling mechanism, comprising a rock drill, a feeding mechanism for the rock drill, a pivot on the feeding mechanism, a pair of support arms swingably attached to the pivot, separate clamps on the support arms for securing the support arms to the rock drill, and means for securing the clamps to the support arms.

FRED M. SLATER. 

